The present disclosure relates to electronic circuits, and more particularly to a digital-to-analog converter.
A digital-to-analog converter (DAC) is an electronic circuit that converts a digital signal to an analog signal. A number of parameters are used to determine the suitability of a DAC for any given application. Among these parameters are the speed at which the DAC performs the digital-to-analog conversion, the resolution of the DAC, as well as the noise generated by the DAC.
A wireless communication device, such as a cellular phone, often uses a high speed, high resolution DAC to convert a digital signal to an analog signal for further processing by the analog circuits disposed in the communication device. Glitches generated in such a DAC increase the noise floor, which in turn may interfere with the signals transmitted by the wireless communication device. One of the main sources of the glitch noise is the delay differences that exist between various stages of the DAC when a transition occurs at the digital input of the DAC.
Low noise, low power, wideband, high resolution DACs are increasingly important for advanced wireless standards, such as the long term evolution (LTE) standard. In radio frequency (RF) applications, the high frequency glitch noise generated by the transmitter DAC is an out-of-band noise that can fall into and desensitize the receiver channel. Controlling the glitch noise in a low-power, high resolution, wideband DAC remains a challenge.